According to the present invention, a method of encapsulating waste material, enabling filling of encapsulent to be carried out less restrictively, comprises charging the material into a container through an opening in the container in an environmentally retricted area, closing the openign with a cover having temporarily closed filling and vent port means to isolate the material, transporting the thus closed container to an encapsulating station, there establishing sealed filling and vent connections respectively with the filling and vent port means and causing simultaneously or thereafter the removal of the temporary sealing of the filling and vent port means while otherwise maintaining isolation of the material, and feeding a solidifiable encapsulating medium into the container through the filling connection to fill space in the container unoccupied by the waste material whilst allowing the atmosphere in that space to be displaced from the container through the vent connection exclusively. The closing of the container opening with the temporarily sealed cover implies total closure of the container such that it may then, in accordance with the invention, be transferred to a less restricted area for the filling with encapsulating medium; the temporary sealing in the cover is not removed until the connections for carrying out the filling and venting have been established so that the isolation of the container contents is maintained.
Advantageously the operation of a connector means to establish the filling and vent connections is effective to remove the temporary sealing so that such removal is not only accomplished in one single operation but is also prevented from occurring prematurely.
It is also advantageous that the connector means should be sacrificial, that is to say, left in place to become an integral part of the resulting monolithic block. To this end, the connector means is conveniently a unitary nozzle having separate passages connectable on the one hand to the filling and vent port means and on the other hand to feed and vent lines; from the latter, the unitary nozzle should be readily detachable so as to be retainable sacrifically in the ports. The filling of the container with the encapsulating medium is continued to the point of ensuring that the nozzle is internally occupied substantially fully by the medium so that on solidification the interior of the nozzle is plugged.
In terms of apparatus, the invention provides a lid or cover by which to close a container holding waste material, such lid having filling and vent port means adapted for the making thereto of a filling connection for the introduction of encapsulating medium and a vent connection for the release of displaced atmosphere, and temporary sealing of the filling and vent port means which is removable simultaneously with or subsequent to the making of the connections. The temporary sealing may be diaphragm arranged to be ruptured by filling and venting nozzle means or similarly may be a disc which such nozzle means can dislodge and eject in being brought into its connected position.